Response to Julian et al. (2015) ‘‘Comment on and Reinterpretation of Gabriel et al. (2014) ‘Fish Mercury and Surface Water Sulfate Relationships in the Everglades Protection Area’’’ Mark C. Gabriel 1 • Don Axelrad 2 • William Orem 3 • Todd Z. Osborne 4,5 Received: 23 December 2014 / Accepted: 30 March 2015 Ó Springer Science+Business Media New York (outside the USA) 2015 Abstract The purpose of this forum is to respond to a rebuttal submitted by Julian et al., Environ Manag 55:1–5, 2015 where they outlined their overall disagreement with the data preparation, methods, and interpretation of results presented in Gabriel et al. (Environ Manag 53:583–593, 2014). Here, we provide background information on the research premise presented in Gabriel et al. (Environ Manag 53:583–593, 2014) and provide a defense for this work using five themes. In spite of what Julian et al. per- ceive as limitations in the sampling methods and analytical tools used for this work, the relationships found between fish total mercury and surface water sulfate concentrations in Gabriel et al. (Environ Manag 53:583–593, 2014) are comparable to relationships between pore water methylmercury (MeHg) and pore water sulfate found in past studies indicating that sulfate is important to MeHg production and bioaccumulation in the Everglades. Julian et al. state ‘‘…there is no way to justify any ecosystem- wide sulfur strategy as a management approach to reduce mercury risk in the (Everglades) as suggested by Gabriel et al. (Environ Manag 53:583–593, 2014), Corrales et al. (Sci Tot Environ 409:2156–2162, 2011) and Orem et al. (Rev Environ Sci Technol 41 (S1):249–288, 2011).’’ We disagree, and having stated why sulfate input reduction to the Everglades may be the most effective means of re- ducing mercury in Everglades fish, it is important that re- search on sulfur and mercury biogeochemistry continues. If further studies support the relationship between sulfate loading reduction and MeHg reduction, sulfur mass bal- ance studies should commence to (1) better quantify agri- cultural and connate seawater sulfate inputs and (2) define opportunities to reduce sulfate inputs to the Everglades ecosystem. Keywords Everglades Á Sulfate Á Mercury Á Fish Julian et al. (2015) provided a detailed evaluation of our publication (Gabriel et al. 2014) and outlined their overall disagreement with our data preparation, methods, and in- terpretation of results. We, however, believe their eval- uation of our paper is flawed and it is in the best interest of the mercury and sulfur research field to defend our work and provide additional supporting information. As stated, the primary objectives of our paper were to (1) compare fish THg (total mercury) and surface water sulfate con- centrations across multiple monitoring stations within the Everglades Protection Area (EvPA) and (2) provide inter- pretation of our results. In support of the original work and interpretation, we first identify how and why the research initiative for our publication was developed. In 2008, at an Everglades Mercury and Sulfur technical meeting held at the South Florida Water Management District (SFWMD), expert & Mark C. Gabriel marklive02@yahoo.com 1 International Joint Commission, 2000 L Street NW, Suite 615, Washington, DC 20440, USA 2 Institute of Public Health, Florida A&M University, 1515 S. Martin Luther King, Jr. Blvd., Tallahassee, FL 32307, USA 3 U.S. Geological Survey, 12201 Sunrise Valley Dr., Reston, VA 20192, USA 4 Wetland Biogeochemistry Laboratory, Soil and Water Science Department, University of Florida, 2181 McCarty Hall A, P.O. Box 11029, Gainesville, FL 32611, USA 5 Whitney Laboratory for Marine Bioscience, University of Florida, 9505 N Ocean Shore Blvd, St. Augustine, FL 32080, USA 123 Environmental Management DOI 10.1007/s00267-015-0486-0